DC system just started trip breaker

[Craig D Peltier]

Hi, I have a Delta 50-760 DC on a 20 amp circuit with nothing else plugged into it. For maybe 4 months it never triggered the breaker but every time now on the first initial startup it trips? When I trip the breaker back there's no probelm on the second startup.

Any ideas? Circuit is only about 5 months old. Could the DC be clogged in some way that its cuasing a surge? When it starts up before an now it takes 5 -8 seconds to get up to speed.

Thanks

[Jason Beam]

Sounds like higher than usual load is on the motor upon startup. Is the filter/bag clean? Is the noise level about the same? Can you spin the motor freely without any noise (Unplugged!)?

In the winter, my air compressor would trip the breaker because it was cold, increasing the start load. This could also be a factor for you - cold motors start harder, usually.

[Kent Fitzgerald]

Craig, DCs are notorious for drawing large startup currents. 60-80A at 120V isn't unusual. Your circuit breaker is designed to tolerate this overcurrent briefly, but breakers do wear, and I suspect that with use and time, the breaker has gotten touchier. You could replace the breaker with a new one, but in the long run, this is a case where wiring the DC and circuit for 240V would make a lot of sense.

[Craig D Peltier]

Sounds like higher than usual load is on the motor upon startup. Is the filter/bag clean? Is the noise level about the same? Can you spin the motor freely without any noise (Unplugged!)?

In the winter, my air compressor would trip the breaker because it was cold, increasing the start load. This could also be a factor for you - cold motors start harder, usually.

Well the DC was empty when this started , means the bag got a inside out beating (thats a messy job). As far as the motor turning easily I will have to take a look.Noise is same.
Thanks

[Craig D Peltier]

Craig, DCs are notorious for drawing large startup currents. 60-80A at 120V isn't unusual. Your circuit breaker is designed to tolerate this overcurrent briefly, but breakers do wear, and I suspect that with use and time, the breaker has gotten touchier. You could replace the breaker with a new one, but in the long run, this is a case where wiring the DC and circuit for 240V would make a lot of sense.

THanks for the tip.
I have one 240 outlet, kinda stinks I have the jointer plugged into it. You suppose the jointer and DC can run off it at the same time? There nearly touching each other an the plug.

[Kent Fitzgerald]

THanks for the tip.
I have one 240 outlet, kinda stinks I have the jointer plugged into it. You suppose the jointer and DC can run off it at the same time? There nearly touching each other an the plug.

Maybe, depending on the capacity of the circuit and the size of the jointer. Really, the best solution would be a dedicated circuit for the DC.

Note that some people (including inspectors) have interpreted the NEC as prohibiting multiple devices on a 240V circuit.